Thanks! I've used that app before but unfortunately without an initial system scan before software installation it doesn't seem to be as thorough as one that takes a before & after snapshot of the system to compare them for differences.
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kleniqMar 27 '11 at 11:48

I am surprised nobody has mentioned AppZapper (which looks great too). You can also opt to use Hazel which sits in the background and helps you when you move an application to the trash by giving you the option to also trash its associated preference files etc.

Hazel also does a lot more. For example, I have Hazel monitor my download folder and labels files according to the amount of time that has passed since I downloaded them. After two weeks, it moves the items to a folder for items scheduled for deletion. After an item has been there for another two weeks, they are automatically moved to the trash.